Ratings FAQ

This FAQ describes the BGA Ratings system and how to use it to decide the grade at which you enter tournaments. Related information can be found at

Contents

Purpose of the ratings pages

How to read the ratings table

How to set your grade

Questions for dan (or nearly) players

General questions

Technical stuff

Purpose of the ratings pages

What are the ratings pages for?

To give UK players information that will help them set their grade when entering tournaments.

All amateurs are weak. Why should we care about our grades?

Many people don’t care, but some do. For those that do care, the BGA seeks to provide meaningful information.

Go tournaments are more enjoyable for everybody if the games are more evenly matched. The only way to achieve this is to match people of the same grade, as far as possible. But this only works if people enter tournaments at fairly accurate grades.

I don’t agree with the strength this page shows for me. Am I obliged to use it?

The BGA has a policy for using the rating pages when entering tournaments. This has been used in the following:

If you're a kyu player then you don't need to use it. There are a few possible reasons why the rating for you may be unsuitable. For example, if you haven’t entered a tournament for some time, but have improved a lot through club or internet games, your rating on this page may no longer be correct for you.

Therefore the rating information is discretionary for Kyu players. The answers below give specific suggestions about how to apply it.

We are asking people to be responsible about this. There are some good reasons to differ from the list, but things like “It’s time I won a prize” (undergraded) or “I feel like a better class of game” (overgraded) are not among them. Remember the basic theme: make yourself and your opponents happy by playing evenly matched games.

Strong kyu players can enter at 1 dan or 2 dan in extreme circumstances if this is agreed in advance with the BGA.

Players with official dan grades are entitled to enter tournaments at that grade, but are encouraged to enter them at a grade equal to the strength listed on the current version of the BGA ratings page, rounded to the nearest whole number. Anyone wanting to enter tournaments outside the range from their official grade to their rounded strength should seek approval from the BGA Council before doing so.

How to read the Ratings Table

How up to date is the Ratings Table?

The data is taken from the European ratings web site at the date shown at the top of the page (sometime during the night), so may be out of sync with the these pages if any tournaments are processed by the ratings website after this. This should be back in sync within 24 hours.

What does the “Grade” column mean?

The grade in this column is the grade the European ratings system last recorded for you. This is the grade at which you entered your last tournament known to the European ratings system, except that, if you entered it at weaker than 20 kyu, the European system records it as 20 kyu. To reflect the fact that they may not be accurate, we display grades of 20K like this.

My grade has changed since I last entered a tournament. Who should I tell?

You do not need to tell anybody, because this column does not affect the calculation of your rating. Just enter the next tournament at whatever is the correct grade for you now, and the next version of the list will reflect your new grade.

What does the “Rating” column mean?

The number in this column is your European rating. It is calculated for everyone who enters tournaments in Europe, from their results in those tournaments. If you would like to know how the calculations are done, you can find details at the European ratings web site.

Note: The EGF ratings system describes a correspondence between ratings and nominal grades, such that a rating of 100 corresponds to a nominal 20 kyu and, for each nominal grade stronger than 20 kyu, the rating goes up by 100. These nominal grades do not correspond well to grades used in practice in Europe. To set your grade, use your strength as described below.

What does the “Strength” column mean?

It shows the European grade equivalent to your rating, calculated from current European data as described in Technical Stuff. For example:

2.0 k...average European 2 kyu
2.3 k...weak European 2 kyu
2.5 k...half way between European 2 kyu and 3 kyu
2.7 k...strong European 3 kyu

And so on.

Strengths weaker than 17.0 k are shown like this to warn you that the figure may be misleading at this level. This is because the European ratings system does not recognise grades weaker than 20K.

What does the “Since” column mean?

This is the date of the last rated tournament you played in—the date when your rating last changed.

What does the “Tours” column mean?

This is the total number of rated tournaments you have ever played in. If you have not played in many tournaments then your calculated rating is probably not very reliable.

How to set your grade

So many numbers! Which are the important ones?

The important number is your strength. It shows the European kyu/dan grade equivalent to your rating.

If I enter tournaments at the grade shown in the strength column, rounded to the nearest whole number, will that be all right?

This will work well for most people most of the time, except those who are weaker than 20 kyu. The questions and answers below will help you to decide whether this is right for you, and you are always welcome to ask for advice.

My strength is shown in red. Should I use it anyway?

You can do so, but at this level there is a risk that the strength figure will be inaccurate and you may end up overgraded. At this level, it is wise to take advice from somebody more experienced who knows you.

I don’t agree with the strength shown for me. Do I have to use it?

No. In a few cases there may be good reasons to differ from the strength shown. The following questions and answers describe some of them. You should do what you believe right.

At the moment somebody else sets my grade for me. Should we go on like this?

Yes. Most of us are slightly optimistic about our own ability at times. It is very wise to take advice from somebody else about your grade.

My strength in the table is much worse than my grade. Is it really that bad? What should I do about it?

There are two reasons why this might happen. The right thing to do depends on which one applies to your case. You can tell which case applies to you by looking at your balance of wins and losses over a period of time.

  • If you are improving rapidly but do not go to many tournaments, your rating, and therefore your strength, may lag behind your playing ability. You can tell if this is the case if you are regularly winning more than you are losing in tournaments. In this case, it is right to ignore the strength column and grade yourself according to recent results.
  • If you have been entering tournaments regularly for some time and your strength is shown as much lower than your grade, you are almost certainly overgraded. In this case you will have been losing more tournament games than you have been winning. The right thing to do is to enter the next few tournaments at a more realistic grade.
  • But beware! The European ratings system can exaggerate overgrading, especially if it has been going on for a long time. To avoid over-correction, it is a good idea to demote yourself cautiously (rounding your strength up rather than down) and monitor your results in the next two or three tournaments. You can always make a further correction (either up or down), if necessary.

Clicking on your name in the ratings list may help you to spot the trend.

My strength in the table is much better than my grade. Is it really that good? What should I do about it?

If you have only just entered the rating system, your European rating, and hence your strength, will not yet be accurate. It would be wise to wait for a few tournaments to see the trend in your ratings movement.

If you have been in the ratings system for a while, and your strength is still much better than your grade, you are almost certainly undergraded and it is time to promote yourself. As in the previous case, be careful, because the European system can exaggerate undergrading if it has existed for a long time. If you feel the strength may be too high, try a cautious promotion first (rounding down rather than up), and monitor the results in your next two or three tournaments.

My strength seems to have quite large swings both up and down. How should I handle this?

Everyone’s strength figure fluctuates like this. Sometimes the swing can be quite large. Remember that the strength figure is calculated from your tournament results.

The most important thing for you to do is to make a realistic assessment of whether your grade is stable or improving. The mistake that people make most often is to treat increases in strength as real improvement, but to put drops in strength down to an off day at a tournament. People who make this mistake tend to be overgraded for most of the time.

There are two ways to avoid this mistake: Keep an eye on your tournament results and your strength over a period of several tournaments, perhaps with the help of your graph linked from the rating list, or get advice from someone you know, or see How to Get advice.

If your realistic assessment is that your playing ability is stable or improving quite slowly, the best approach is to be cautious in promoting yourself. Try to get evidence from the results of two or three tournaments (more, for the stronger kyus) before promoting yourself. This way, your promotions will be realistic, and then there is no need to worry about the fluctuations that you may see from time to time.

I didn’t go to any tournaments recently, but my strength has changed slightly. Why is this, and what should I do about it?

This can happen as a result of small variations in the European ratings as a whole. You should ignore it.

I play as X kyu in the club and get about even results, but my strength in the table is very different from this. Why shouldn’t I just use my club grade?

This list is concerned with tournament entry grades rather than club grades. Club grades are an unreliable indicator of tournament entry grades because:

  • Club grades are often shifted away from the national averages.
  • Club games are played under different conditions from tournament games. For example, people may be allowed to take back silly moves; people may be distracted by other things going on at the meeting place; and so on.
  • People very often learn to deal with the styles of the people they play frequently, causing them to play better against these opponents than they do against the wider range of opponents they meet in tournaments.

My strength in the table is wildly different from my rating on the Go server I use. What should I do?

Gradings on Go servers are very different from European gradings. You should use this list when entering tournaments in the UK and Europe, but use your server rating when playing on a server.

My strength is shown as 0.7d. Can I enter tournaments as 1 dan now?

Yes. All players are welcome to enter tournaments at their strength, rounded to the nearest whole number. This includes entering tournaments at dan grades.

Questions for dan (or nearly) players

The table shows my strength as much higher than my grade, but I’m not being promoted. Have I been forgotten?

You are encouraged to enter tournaments at a grade equal to your strength rounded to the nearest integer. If you have not been given an official BGA grade reflecting your current strength, it should either be because you have not met one of the criteria for awarding BGA dan certificates, or because the BGA Council has not met since you did attain these criteria.

However, if you suspect that you might have been overlooked, please contact the BGA Secretary and we will review your case.

I’m a dan player, but I’m playing below par. What should I do?

Just like everyone else, dan players have their ups and downs. One could be playing below par temporarily for all the usual reasons. We recommend that you enter tournaments at a grade equal to your strength rounded to the nearest integer.

How does the dan grading committee operate?

The dan grading committee was dissolved when the current system for awarding BGA dan certificates was adopted in January 2004. The page How the grading committee works has been retained for historical interest, but the system it describes is no longer in operation.

There is a list of dan diplomas awarded by the BGA.

General questions

Why don’t I appear on the list?

You only appear on the list if you have played in a rated tournament within the last 24 months.

Note that a few tournaments are not considered by the European rating system, because they don’t meet criteria laid down by the EGF for inclusion in the ratings.

Also, remember that only UK players are included in the list.

My name/club in the list is wrong. Can it be fixed?

Yes, it can, but if possible it is better to get it right first time. The name and club information in the list comes from tournament results. When you play in a tournament, take a moment to check your details on the results list during the day, and if there are any errors ask the tournament organiser to correct them.

If incorrect details do get onto the list, then to get them corrected you need to contact the Tournament Results Officer. He will get the correction made, but it will not appear until the next rating list is published by the EGF (please allow several weeks for this).

Also, if you are not a member of a club, or live in a place with no Go club, please specify the name of the nearest town to where you live as your “club” when entering tournaments.

Why doesn’t it take club games into account?

Club games can be misleading for several reasons. See Why shouldn’t I just use my club grade?.

Why doesn’t it take the game score into account?

Doing this actually distorts the game. For example, a player who is behind may run extra risks to try and catch up. If we take the game score into account, people may be tempted to play, not to win, but to minimise their loss.

Why don’t we enter tournaments on the basis of European rating rather than on grade?

There are three reasons:

  • For a significant minority of people, their rating is misleading. It would be unfair to force those people to enter a tournament at an inappropriate rating.
  • It is impractical to arrange the draw on the basis of European ratings. Tournament organisers already have a complex project on their hands, and asking them to access European data for the tournament is just not feasible.
  • To discourage tournament directors from over-tuning the draw, possibly causing people to get the same opponents more often, rather than the variety of opponents we all want.

Someone is trying to enter my tournament at a grade different from their official strength. What should I do about it?

If the grade is a kyu one or it's a foreign player you should accept the entry at the grade claimed. Changing the grade at which people enter tournaments is strongly deprecated.

If it's for a dan grade for a UK player and above their official strength or official grade then ask them if they have permission from the BGA to do so. If it's at a level above 2 dan, then it's extremely unlikely that permission will have been given. If they can't confirm such permission then they should be entered at their official strength or 1 Kyu at best.

Be careful when making judgements about other people’s grading. Numbers are not everything. As shown above, there can be good reasons for grade to differ from ratings in a number of cases. A likely result of changing people’s entry grades would be to discourage entries from people in this position.

I’m still not sure what to do. Who can I ask for further advice?

The best advice would probably be from an experienced player who knows you. Any member of the BGA Council will be also happy to help you.

Technical stuff

How are the ratings calculated?

The BGA rating list is based on the European Rating List, produced by the EGF. It is updated daily to include results submitted that day. The European Go Ratings web site includes a description of how the system works.

How are the strengths calculated?

Each time a new European list is published, we download it and calculate the linear regression of rating against grade for the whole of Europe. This straight line fit gives us a method for converting a rating into a corresponding fractional grade. This fractional grade is the strength.

For those who would like to know the formula, your strength is:

strength = (rating - r) / g

where

  • r is the rating for an average shodan on the grade/rating line.
  • g is the difference in rating corresponding to a one-grade difference on the grade/rating line.

The values of r and g in this formula change slightly over time depending on the behaviour of all go players in Europe. The current values are stated below the ratings table.

When is the rating list updated?

The whole update procedure is performed automatically by a script that runs overnight. So even if you are desperate to to discover your new rating, there is no point checking the list more than once per day.

Can I get a copy of my past strength?

Yes. If you click on your name in the rating list, you will be taken to a page containing a graph of your entire rating history.

Also, The European ratings web site provides a file containing the complete ratings history for every person who has ever been in the system. This is a zipped text file. Before you can read it, you will need to unzip it.

What's a rating reset?

The European rating system evaluates results of tournaments using the previous grade achieved by a person if they appeared in the system previously (the entry rating). This means that the rating for rapid improvers will trail the actual strength of the player. To compensate for this if a player enters a tournament two or more grades above the previous tournament then their entry rating is set to the rating for that entry grade, e.g. if you enter at 2 kyu and in the previous tournament you had entered at 4 kyu then your entry rating will be set to 1900.





Last updated Thu Aug 29 2013. If you have any comments, please email the webmaster on web-master AT britgo DOT org.